A Tagging-via-substrate Approach to Detect the Farnesylated Proteome Using Two-dimensional Electrophoresis Coupled with Western Blotting*□S

Prenylation is a post-translational modification critical for the proper function of multiple physiologically important proteins, including small G-proteins, such as Ras. Meth-ods allowing rapid and selective detection of protein far-nesylation and geranylgeranylation are fundamental for the understanding of prenylated protein function and for monitoring efficacy of drugs such as farnesyltransferase inhibitors (FTIs). Although the natural substrates for pre-nyltransferases are farnesyl pyrophosphate and gera-nylgeranyl pyrophosphate, farnesyltransferase has been shown to incorporate isoprenoid analogues into protein substrates. In this study, protein prenyltransferase targets were labeled using anilinogeraniol, the alcohol precursor to the unnatural farnesyl pyrophosphate analogue 8-ani-linogeranyl diphosphate in a tagging-via-substrate ap